Answer:
Explanation:
Kinetic energy generated = work done by force = force x displacement
= 3 x 7 = 21 J
Answer:
The last graph.
Explanation:
Gravitational potential energy is the energy possessed by a body at a given height from the Earth's surface.
The formula to find the gravitational potential energy is given as:
Where, 'U' is the gravitational potential energy.
'm' is the mass of the body.
'g' is the acceleration of the body due to gravity.
'h' is the height of the body above the Earth's surface.
So, from the above equation, it is clear that, gravitational potential energy is directly proportional to the height. So, as height increases, the gravitational potential energy increases. At the surface of Earth, where, height is 0, the gravitational potential energy is also zero.
Therefore, the correct graph is a straight line with positive slope and passing through the origin. So, the last option is the correct one.
Answer:
The correct option is A = 1960 N/m²
Explanation:
Given that,
Mass m= 20,000kg
Area A = 100m²
Pressure different between top and bottom
Assume the plane has reached a cruising altitude and is not changing elevation. Then sum the forces in the vertical direction is given as
∑Fy = Wp + FL = 0
where
Wp = is the weight of the plane, and
FL is the lift pushing up on the plane.
Let solve for FL since the mass of the plane is given:
Wp + FL = 0
FL = -Wp
FL = -mg
FL = -20,000× -9.81
FL = 196,200N
FL should be positive since it is opposing the weight of the plane.
Let Equate FL to the pressure differential multiplied by the area of the wings:
FL = (Pb −Pt)⋅A
where Pb and Pt are the static pressures on bottom and top of the wings, respectively
FL = ∆P • A
∆P = FL/A
∆P = 196,200 / 100
∆P = 1962 N/m²
∆P ≈ 1960 N/m²
The pressure difference between the top and bottom surface of each wing when the airplane is in flight at a constant altitude is approximately 1960 N/m². Option A is correct
<h3>
Answer:</h3>
189.07 kPa
<h3>
Explanation:</h3>
Concept tested: Boyle's law
<u>We are given;</u>
- Initial volume of the syringe, V1 is 16 cm³
- Initial pressure of the syringe, P1 is 1.03 atm
- New volume of the syringe, V2 is 8.83 cm³
We are required to calculate the new pressure of the syringe;
- We are going to use the concept on Boyle's law of gases.
- According to the Boyle's law, for a fixed mass of a gas, the pressure is inversely proportional to its volume at constant temperature.
- At varying pressure and volume, k(constant) = PV and P1V1=P2V2
Therefore, to get the new pressure, P2, we rearrange the formula;
P2 = P1V1 ÷ V2
= ( 16 cm³ × 1.03 atm) ÷ 8.83 cm³
= 1.866 atm.
- Thus, the new pressure is 1.866 atm
- But, we need to convert pressure to Kpa
- Conversion factor is 101.325 kPa/atm
Thus;
Pressure = 1.866 atm × 101.325 kPa/atm
= 189.07 kPa
Hence, the new pressure of the air in the syringe is 189.07 kPa
